This invention relates to the field of testing for the concentration of organic compounds in liquids, and more particularly, to a method and apparatus for continuously measuring the concentration of organic compounds in an aqueous solution.
Considering the present environmental problems involving both waste disposal and its effect upon the quality of water, it is necessary to test groundwater, water supplies, waste water and/or industrial liquid waste to determine the concentration of any contaminants therein. It is desirable to continuously measure liquids for the concentration of organic compounds in order to minimize the deleterious effects of these contaminants in water and to maintain and improve the quality of our water supplies. Many non-purgable hydrophobic organic compounds are known to contaminate water supplies. Polychlorinated biphenyls (PCBs), polynuclear aeromatic hydrocarbons (PAHs), dioxins, petroleum materials, and pesticides, for example, are just some of these commonly known organic compounds.
There are currently available modern analytical instruments which are capable of detecting and quantifying minute amounts of organic compounds. Presently, however, the testing of water and other liquid solutions for the presence of organic compounds is commonly performed in a non-continuous, non-real time manner where samples of water are transported to various testing apparatuses. This procedure, however, is labor intensive and is usually performed in the laboratory.
One problem with the current testing and measurement of organic compounds in water is that the concentration of these organic compounds in water may be minute making it difficult for analytical devices to accurately measure the concentration levels. As a result, it is frequently necessary to increase the concentration of the organic compounds in order to measure their concentration. In these situations, an organic solvent extract containing organic compounds is typically evaporated off-line and then analyzed to determine concentration levels. Hollow fiber membranes have been used in industrial extractors and pervaporators. However, it is desirable to utilize a system which operates as an analytical sampler/extractor/concentrator to provide continuous on-line measurements of the concentration of organic compounds utilizing non-porous hollow fibers.
It is, therefore, an object of the present invention to provide a method and apparatus for measuring the concentration of organic compounds in aqueous solutions which can be accomplished in the field.
It is also an object of the present invention to provide an apparatus for measuring the concentration of organic compounds which will provide a real-time, on-line continuous measurement of the concentration of organic compounds in water, waste water and industrial liquid waste.
It is also an object of the present invention to provide a method and apparatus for measuring the concentration of organic compounds in an aqueous solution which may provide accurate and reliable measurements of the concentrations of such organic compounds.